ght which they emit. But a more singular phenomenon connected with this phosphorescence is that the colours vary instantaneously, passing rapidly from the most lively red to the principal tints of the solar spectrum, to the crimson of the morning, to orange, to greenish, to azure blue, and finally to opaline yellow, when the mass is, to all appearance, in a state of absolute repose. Bibra relates, in his "Travels in Chili," that he once caught half a dozen pyrosomas, by whose phosphorescence he could distinctly read their own description in a naturalist's vade-mecum (or pocketbook). Although completely dark when at rest, the slightest touch sufficed to elicit their clear blue-green light.

Another order of phosphorescent animals belonging to the tunicata, but not to the ascidians, is the “salpæ,” creatures of great delicacy of organization, and so transparent that the interior structure may be examined through the tunic with little difficulty. The bands which they form are among the most brilliant of those luminous tribes which occasionally give such a sparkling lustre to the waters of the ocean. The salpæ, when thus chained together, produce the effect of long ribands of fire, sometimes drawn straight in the direction of the currents, sometimes twisted and almost doubled by the waves.

to the motion of the ship. They appeared, however, to extend deep; and in all proba bility were of a similar character to the immense aggregations of close-packed swimming invertebrata (animals without a backbone) so well known to mariners in Arctic regions under the appellation of ". whalefood." Each of these salpæ measured about half-an-inch in length. but so close was their accumulation that of the quantity collected by the sudden plunge of an iron-rimmed towing-net, half the cubic contents, after the water had drained off, generally consisted of nothing but one thick gelatinous pulp.

They form the chief food of millions of voracious fishes, but in their lifetime they have had their good things and feasted on "foraminifera," diatornacea," &c. Their intestinal tube is so slender and friable that it withers at the human touch, and yet the microscope reveals within it the keen flinty needles of sponges, chalky shells of foraminifera, and other sharp substances, which appear to do it no harm.

The salpæ deserve especial attention for the remarkable circumstance attending their reproduction, and which, for want of a better term, is called the alternation of generations. They are found, as we have seen, in long chains, gliding snake-like through the water, as if obeying a single will, and they are also found solitary or separate. The wonderful thing is that these two forms, so different in outward appearance, are only the alternating generations of one and the same animal. The chained salpæ produce only solitary ones, and the latter only chains; or, as Chamisso expresses it, a salpæ mother never resembles her daughter or her own mother, but is always like her sister, her grand-mother, or her grand-child! It is to Chamisso we owe the discovery of the interesting fact, and when he first made it known he was laughed at as a fanciful visionary. Later observations have not only fully confirmed his statement, but also discovered similar wonderful metamorphoses among the jellyfish, polypi, crustacea, sea-urchins, and other marine animals.

Unlike so many of the tunicata, the salpæ are swimmers in the wide and open sea, visiting our coast so rarely that we can scarcely reckon them as properly British animals. They are most abundant in tropical climates. Messrs. Quoy and Gaimard relate having seen on one occasion, not far from the Cape of Good Hope, long zones of a reddish-brown colour traversing the surface of the ocean, as far as the eye could reach. These were found on examination to consist of minute salpæ, aggregated together in bands. Dr. Wallich speaks from his own experience when he says that between the Cape and St. Helena, for many degrees of latitude, the ship passed through vast layers of sea-water so thronged with the bodies of a species of salpæ as to present the consistence of a jelly. These layers extended for several miles in length; their The last class of molluscous animals is depth it was impossible to ascertain, owing the "Polyzoa," called also the "Bryozoa,"

1

the former name being applied to them be- | trough of sea-water, be examined with a cause they are always compound animals. microscope, the spectacle is most wonderThey bear such a close resemblance to the ful! The eye is bewildered, says Mr. Gosse, polypes, a class of radiated animals, that and the mind amazed, at the sight of scores they were long regarded as belonging to of naked skulls swinging to and fro, not them, and it is only of late years that natu- evenly and uniformly, but fitfully and, as it ralists have found reason to give their appears, wilfully; while the yawning gape present place. The difficulty is not to be of the mandibles to an awful reach, and wondered at when we remember that they ever and again the spiteful snapping of the are so small as to require a microscope to lower into the groove formed by the formake them out, and grow on shells, rocks, midably-toothed edges of the upper, make sea-weeds, &c., under the water. Spring- us involuntarily shrink and shudder, lest the ing, as most of them do, from a creeping vicious bite should take a piece out of our root-thread, in the form of a tiny shrub, flesh. composed of successive series of pellucid cells, from which little animals protrude, each creature surmounted by a coronet, of radiating tentacles, all connected so as to have a common life, they do indeed bear great external resemblance to the polypes. Yet when the animals themselves are examined, they are found to be of a higher grade than the radiata, and worthy to class with the mollusca. Their chief peculiarity is the possession of tentacles having cilia (or hair-like appendages), by whose action a sort of vortex is produced in the water, carrying minute animals down into the mouth. Many of the genera are furnished also with appendages bearing a remarkable resemblance to the head of a vulture, and hence commonly called "bird's-head organs." They consist of an upper and a lower piece, the upper one being the larger; and both together nod to and fro, occasionally opening wide the mandibles, and closing them with a powerful snap, apparently with great exercise of will and discrimination. Mr. Darwin experimented on some, and found that when touched with a needle, the beak generally seized the point so firmly, that the whole branch might be shaken.

There are species in which the resemblance to the entire skull of a bird is most marked and striking. In these the organ is attached by a hinge-joint, which permits great freedom of motion. A shelly knob is placed on the outside of the cell, and on this is seared the mimic skull, which sways backward and forward, just as a head does upon the spine. If one of these shrubby polyzoea, in full health and vigour, in a

The office of these singular appendages is by no means satisfactorily made out. They have been supposed by some writers to serve for the protection of the colony, of which they form a part, by keeping off the attacks of other marine animals; whilst others have considered them as purveyors of food, small animals being often captured by them. Against the idea that they serve this latter purpose, it might be urged that they are placed outside the cell, and no communica tion exists between this ferocious mouth and the stomach of the animal within. But Mr. Gosse has suggested that it may act as a trap to capture minute animals, which being grasped tenaciously till they die, may be a means of attracting the proper prey to the vicinity of the mouth. The presence of decomposing animal substance in water invariably attracts crowds of infusory animalcules, which then breed with amazing rapidity, so as to form a cloud of living atoms around the decaying body; and these remain in the vicinity, playing round and round, until the organic matter is quite consumed. Now a tiny annelid or other animal, caught by the bird's-head of a polyzoan and tightly held, would presently die; and though it would not itself serve as food to the capturer, yet by becoming the centre of a crowd of busy infusoria, multitudes of which would constantly be drawn into the vortex made by the cilia around the mouth, it would contribute to the animal's support. Thus the action of the bird's-head may likened to that of a man who over-night scatters ground-bait about the spot where on the morrow he intends to fish.

be

Dr. Carpenter, speaking of the polyzoan | weeds, carefully examine them with finger called Bowerbankia, says that considerable and glass, and if the multitude of small power of selection appears to be enjoyed horny cells be detected, put the thing (a by the animal in regard to its food. The polypidom, it is called) into a vessel of seamovements of the cilia, which are thickly water, and you may see the polyzoa a little set on the ten tentacula (feelers) arranged protruding their tentacles. round the mouth, seem entirely under the control of the will of the animal; and by their vibrations currents of water are produced which bring particles of various kinds of living and dead matter to the mouth. It has been sometimes noticed that animalcules which have thus been drawn into the throat escape during the act of swallowing; but they are usually met by one of the tentacula, which bends inwards, and by means of a sharp blow drives them back into the mouth. They do not immediately perish in the stomach, but may sometimes be seen to continue their movements for a good while within its cavity.

Those who have spent a few days at the sea-side must have often picked up specimens of flat-lobed, plant-like-looking bodies, which, when examined with a good magnifying glass, are found to be full of little cavities. These are sea-mats, or flustra, and each little cell is the house of a polyzoan. They so much resemble common sea-weed in appearance that they are often mistaken for them by ignorant collectors. They may be purchased at the sea-side, arranged with sponges, polypes, and corallines in bouquets. Apart from the visibility of the cells on a close examination, the sea-mats may be distinguished from sea-weeds by the crispness of their feel; the sea-weeds, on the contrary, feeling flabby. This crispness of feel, or rough, harsh, stony sensation, experienced on passing the fingers over the surface of the flustra, is caused by the innumerable spine-crowned cells before mentioned. The lens shows them to be arranged in rows something like the scales of a fish, or tiles on a house-top. Each cell is armed with four short, sharp spines, projecting from the upper portion of the edge, two on each side. The cells are placed back to back like those of a honeycomb, so that there is no right or wrong surface to the flustra-leaf. The next time you go to the sea-side and pick up what you suppose to be pale brown sea

The sea-mats multiply by buds, developed from the outer surface of the cell. From one original cell five such buds may be sent off, which become new cells around the first, and in their turn produce buds from their unattached edges. In this way the extension may go on almost without limit, and it often happens that after the cells in the centre of the leaf have lost their inhabitants by death, the edges are in a state of active growth. The animals are usually packed closely together, and being very small must number enormous multitudes o a very moderate surface. Dr. Grant has reckoned that on an ordinary specimen of flustra carbasea there are about ten square inches of surface, and in each square inch about 1,800 cells, thus making altogether 18,000 within this small space.

And then the numbers of the cilia! Each little animal has 22 tentacula, so that there will be about 396,000 of these minute arms upon one little specimen of ten inches surface. If each of these tentacula has only 100 cilia upon its edges (and there are probably many more), the whole polyzoary will have 39,600,000 of these minute but important organs. Other species certainly contain more than ten times these numbers. Dr. Grant has computed about 400,000,000 cilia to exist on a single flustra foliacea. The CC sea ragged staff," so called by John Ray, is a common form of these polyzoa, often cast on our eastern coasts in great abundance after a storm. It is in the form of smooth-branched gelatinous masses, having something of the appearance of barleysugar. The little molluscs which inhabit this fleshy recess shrink down into its interior as long as thev are exposed to the air, but on being put into water, if not too much damaged, they may be coaxed into expanding their beautiful tentacles.

Almost every sea-weed of any size will be found partially covered with the cells of the "lepralia," which are not unlike those of

the sea-mate. Their appearance is that of a kind of stony scurf spread evenly over the substance of the sea-weed, and often so thickly that there is hardly a spot left uncovered. There are nearly 40 British species of this single genus lepralia; the chances are that if you pick up half-a-dozen specimens, three or four of them will be distinct species. Mr. Busk has divided them into

(1) those furnished with bird's-heads, (2) those furnished with whips, and (3) those with neither of these appendages.

Some of the polyzos inhabit fresh water, and are occasionally to be found in London cisterns, their eggs having been brought up in the water from the Thames. The eggs are very beautiful objects under the microscope.

THE TOY OF THE GIANT'S CHILD.

FROM THE GERMAN OF HIS LATE ROYAL HIGHNESS THE PRINCE CONSORT.
IT is the lofty Insellberg-a mountain high and strong-
Where once a noble castle stood-the giants held it long; :
Its very ruins now are lost, its site is waste and lone,
And if he looks for giants there, they are all dead and gone.
The giant's daughter once came forth, the castle gate before,
And played with all a child's delight before her father's door;
Then sauntering down the precipice, the girl would gladly go,
To see, perchance, how matters went in the little world below.
With few and hasty steps she passed the mountain and the wood,
At length approaching near the place where dwelt mankind she stood;
And many a town and village fair, and many a field so green,
Before her wondering eyes appeared, a strange and curious scene.
And as she gazed, in wonder lost, on all the scenes around,
She saw a peasant at her feet a-tilling of the ground;
The little creature crawled about so slowly here and there,
And lighted by the morning sun, his plough shone out so fair.

"Oh, pretty plaything!" cries the child, "I'll take thee home with me."
Then with her infant hands she spread her kerchief on her knee,
And cradling man, and horse, and plough so gently on her arm,
She bore them home quite cautiously, afraid to do them harm.

She hastes with joyous steps and glad (we know what children are),
And spying soon her father out, she shouted from afar-
"Oh, father! dearest father! what a plaything I have found!
I never saw so fair a one upon our mountain ground!"

Her father sat at table then, and drank his wine so mild,
And smiling with a parent's smile, he asked the happy child—
"What struggling creature hast thou brought so carefully to me?
Thou leap'st for very joy, my girl! come, open, let us see!"
She oped her kerchief cautiously, and gladly you may deem,
And showed her eager sire the plough, the peasant, and his team;
And when she'd placed before his sight the new-found pretty toy,
She clasped her hands, and screamed aloud, and cried for very joy.
But her father looked quite seriously, and shaking slow his head,
"What hast thou brought me here, my girl ?-this is no toy," he said.
"Go take it to the vale again, and put it down below:

The peasant is no plaything, child! how could'st thou think him so?

"So go, without a sigh or sob, and do my will," he said:
For know, without the peasant, girl, we none of us had bread;
'Tis from the peasant's hardy stock the race of giants are
The peasant is no plaything, child,—no, God forbid he were!”

A

CAROLUS VON LINNE.

COMMONLY CALLED LINNEUS.

S society increases in means, and nations | His fame now advanced; he was looked up progress in civilization, mankind be- to as a promising genius of some brilliancy; come more enlightened. It is then scientific so much so that the Academy of Sciences at research acquires a value, and obtains a posi- Upsal sent him, in 1732, to make a tour of tion deeply interesting. As we advance in botanical investigation through Lapland. knowledge, we habitually learn to be inquisi- The Swedish people do not appear to be so tive respecting the origin of those things by lavish in their allowances on these occasions which we find ourselves surrounded; we be- as some other, perhaps more wealthy, nations: eome anxious to dive into the arcana of the whole amount apportioned to Linné for nature; we grow impatient to ascertain the this object not being more than fifty Swedish laws by which her operations are conducted, dollars, which were deemed amply sufficient and our energies are directed to wrest from to defray his expenses; and with this comher bosom, if possible, her secrets. Those paratively small sum, unaccompanied by any individuals, therefore, who strive to aid us one, he prosecuted a journey of three thouin such our endeavours, by the invention of sand five hundred miles, from which he reingenious theories, must always hold a con- turned at the end of the year. He was next sequential rank among naturalists. We engaged in a scientific tour through Dalecarlia, hail as benefactors of no common worth all and went again to Lapland on a mineralo. those who devote their time, employ their gical discovery. In 1735, he published a talent, and bring their genius to bear upon highly classical work, the complete Flora of such desirable purposes. They are indeed, Lapland; subsequently, his Rudiments of in the truest sense of the word, the friends Botany, in which he laid down the basis of to their species; we accept their assistance his own system, attracted the notice of Mr. with gratitude, and every occurrence relating Clifford, a wealthy merchant residing at to them is considered worthy of our parti- Amsterdam, who made him the superintencular notice. dent of his garden at Hartecamp, near Haerlem, then famous for its curious and valuable collection of exotics, of which our botanist drew up a systematic catalogue. In 1738, Linné visited England, after which he made an excursion to Paris, and towards the close of the year returned to his native land, where he settled as a physician at Stockholm. About this time the Swedish Government established a Royal Academy in that city, of which Linné was one of the first members, who very materially contributed to its character, and greatly advanced his reputation by the opportunities thus offered to him to display his abilities, now considered among scientific men to be of the very first order. In 1741 he succeeded to the professor's chair for medicine in the University of Upsal, and was also made superintendent of the botanic garden, to the augmentation of which, and to bring it under the new arrangement conformably to

This celebrated naturalist was born 13th May, 1707, old style, at Roshult, in the province of Smaland, in the kingdom of Sweden, and put apprentice to a shoemaker. Dr. Rothmann, a physician, perceiving the lad to possess considerable talent, interfered with his parents, and prevailed upon them to let him study for the practice of medicine. In consequence of this arrangement, he entered at the University of Lund, in Scania, in 1727, whence he removed the year follow. ing to that of Upsal.

It was here he conceived the idea of a new arrangement of plants, now known as the sexual system; to the furtherance of this purpose he wrote a memoir, which was shown to Rudbeck, the botanical professor, who was so struck with its ingenuity that he received the author into his house, as a tator to his children, and made him his assistant in the delivery of his lectures.